As New Zealand's Olympic rowing heroes ponder their futures in the sport, top officials have warned it is going to be difficult to wave tempting pay rises under their superstars' noses.

At the moment Kiwi rowing's top performers, such as gold medal winners Mahe Drysdale, Eric Murray and Hamish Bond, are paid $60,000 a year through High Performance Sport NZ's Performance Enhancement Grant (PEG) programme. Any more tends to be through individual sponsorship arrangements, which are thin on the ground.

That's a paltry amount when compared to the big sums earned by New Zealand's professional rugby and league players, many of whom are also able to top up their deals with lucrative private sponsorships.

And as so many of the national squad members ponder their futures, it does not appear that the financial carrot can be waved to entice the top performers through to Rio.

Rowing NZ's chief executive Simon Petersen, in London for the Games programme, admits his hands are tied in terms of the financial support he can offer.

He says unless corporate sponsors decide to jump on board the sport - a possibility after a Games regatta in which the likes of Drysdale, Bond, Murray and double-scullers Nathan Cohen and Joseph Sullivan have become household names - RNZ is limited to the PEG grants provided by HPSNZ.

“You always want to pay your athletes more, but there's only so much money,” said Petersen.

Having far exceeded targets, RNZ is keen to pitch an eight-year funding programme to HPSNZ, and look at the prospect of competing in all 14 Olympic classes. “We've got to make sure we capitalise on this success, and we have the depth and sustainability to deliver in Rio and 2020,” said Petersen.